I think Hewitt will leave the DoH, not something I would have confidently stated a. month ago

As a paid-up member of the Keep Calm Tendency I'm rarely as alarmed or surprised about unfolding events as some of my colleagues. But home secretary John Reid's decision to leave the cabinet when Tony Blair goes caught me off guard too.

Mr Reid may no longer be health secretary, but his departure to 'recharge his batteries' (what can that mean?) makes it much easier for Gordon Brown to engage in a sweeping reshuffle of the cabinet he inherits - Patricia Hewitt included.

I think she will leave the DoH, not something I would have confidently stated a month ago. Prime minister Brown must combine continuity with change and the DoH is one of those high-profile departments where change may be appropriate.

Although I missed the King's Fund Blair-fest (news, page 7, 3 May) I had two reasons to think of Mr Reid and Labour's NHS decade when I was in Scotland covering the elections from which the SNP emerged narrowly ahead. Don't panic: they're not going to do anything silly.

One thought came when a businessman in Dundee railed against Scotland's pioneering ban on smoking in public places. 'Labour has lost touch with its roots.' Pub and bingo profits are down, tobacco sales are up and people are forced to smoke at home with the kids, he said.

That is just as Mr Reid warned when he lost the battle for a compromise in cabinet in 2004-05. Yet at the King's Fund Mr Blair praised the ban as one of Ms Hewitt's achievements. You can see it both ways. Who's right? Health obviously, but politics pay a price.

My second thought was also unsettling. Listening to Messrs Blair and Brown warning Scotland that an SNP vote would be a vote for chaos and separation, rather than for a change of team, reminded me of the '24 hours to save the NHS' stuff they hurled at John Major in 1997.

At the King's Fund, Mr Blair mentioned that slogan unapologetically after a series of heavyweight witnesses had given the government creditable marks for what it had done to 'save the NHS' - as HSJ's 3 May editorial confirmed. There was also criticism but the tone was constructive, as you can judge on the Number 10 website: it can all be read verbatim if you are not too busy improving NHS productivity.

If only all such public discourse could be so civilised. Reading health minister Andy Burnham's 10th anniversary attack on the 'grim' 1979-97 record - 'Tories wrecked the NHS, Labour has rebuilt it' - I flinched. At least I did until I read shadow health secretary Andrew Lansley's counter-attack on NHS staff levels, 27,000 off their peak of 1,366,030 - 'the direct result of Brown's failures,' the Tory spokesman thundered.

As with Blair-Brown efforts to terrify the Scots I'm not convinced that sceptical voters buy this Dr Punch and Nurse Judy stuff any more, although I suppose it did close the Labour-SNP gap north of the border. But nor do I think voters will embrace the Reform lobby's latest health insurance ideas or this week's British Medical Association warnings about rationing relatively minor treatments. When President Sarkozy starts looking hard at France's magnificent but bankrupt health insurance system we may grudgingly admire our own tax-funded ways a little better.

Health historians may conclude that it was John 'Targets' Reid (2003-05) who bore down on the waiting-list ambitions he inherited from Alan Milburn (1999-2003). They were crucial to the 'investment and reform' strategy of the NHS Plan (2000-2010) and the NHS Cash (2003-08), not to mention NHS Choice and Competition theory.

In Labour's own pantheon Frank Dobson (1997-99) gets an honourable place as the man who put the National back into NHS by way of NICE and the national service frameworks, someone reminded me this week. He also pioneered Brownite private finance initiative hospital building, something he may not love so much today.

Where does that leave the Hewitt legacy? Apart from the smoking ban, as the woman who sorted out those rackety trust budgets, her supporters would say. And who will get her job consolidating all this on 3-4 July? Guessing is a mug's game; Tessa Jowell would love it. Hilary Benn perhaps? Young Liam Byrne or younger Mr Burnham? It's a tough post and Mr Gordon is cautious: expect the winner to have grey hair.

Michael White is assistant editor (politics) of The Guardian